This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A033093 #12 Nov 14 2012 18:06:20
%S A033093 0,1,1,3,2,3,1,5,5,5,3,6,2,3,3,8,5,9,5,8,5,4,2,9,5,5,7,9,5,8,2,11,9,8,
%T A033093 8,13,6,7,6,11,5,9,3,7,8,5,3,13,7,10,8,9,5,12,7,11,6,5,3,13,3,4,6,15,
%U A033093 12,14,8,11,9,12,6,18,8,9,11,11,9,11,5,14,13
%N A033093 Number of 0's when n is written in base b for 2<=b<=n+1.
%H A033093 Grant Garcia, <a href="/A033093/b033093.txt">Table of n, a(n) for n=1..10000</a>
%F A033093 Conjecture: lim inf a(n) = infinity. The lim inf grows quite slowly: e.g. a(2047)=7. Weaker conjecture: 2, 3 and 7 are the only n for which a(n) = 1. Note that a(n)=1 implies n=2 or n=2^k-1; probabilistically, the chance that 2^k-1 has no zeros just in base 3 is C^k, where C = (2/3)^(log(2)/log(3)) ~ .774, so the number of exceptions should be finite. It appears that 2^15-1 is the last n with no zeros in either base 2 or 3 (and it does have zeros in base 5). - _Franklin T. Adams-Watters_, Nov 07 2005
%F A033093 G.f.: (Sum_{b>=2} (Sum_{k>=0} x^(b^(k+1))/(Sum_{0<=i<b} x^(i*b^k)))/(1-x)) - _Franklin T. Adams-Watters_, Nov 07 2005
%t A033093 f[n_] := Count[Flatten@ Table[ IntegerDigits[n, b], {b, 2, n + 1}], 0]; Array[f, 90] (* _Robert G. Wilson v_, Nov 14 2012 *)
%Y A033093 Cf. A033094, A033095, A033097, A033099, A033101, A033103, A033105, A033107, A033109, A033111.
%K A033093 nonn,base
%O A033093 1,4
%A A033093 _Clark Kimberling_